The effectiveness of written feedback on writing is influenced by various variables, including students proficiency levels, prior learning experiences, expectations and educational contexts. Although thai students are reported to have serious problems in english writing, which are partly caused by their culturally-based english learning styles, few studies have been conducted to find out how teachers assist them through their feedback. This study thus reports on the practice of teacher feedback in terms of its forms, locations, types and purposes with a consideration of several influential factors in an essay writing class at a university in thailand. Furthermore, the levels of the students reactions to the teacher feedback, the effects of their revisions and their revision strategies were also examined. To learn about these students opinions on the effectiveness of the feedback strategies employed, a survey with the whole class and a focus-group interview were also conducted at the end of the course. The results showed the students active engagement in responding to the teacher feedback, and this tends to assert the crucial roles of teachers knowledge of students learning experiences, english proficiency levels, feedback preferences and classroom settings on the success of written corrective feedback. Though the findings might not be generalized in other efl settings, they show how in-service teachers adjust feedback strategies in their actual teaching situations to prepare efl students to become self-regulating writers. 2019, Universiti kebangsaan malaysia press. All rights reserved.